Which throw exactly are we talking about here? Seoinage? The problem I see quite a lot with people on that throw is that they do not come in tight enough to uke, so they are pulling uke towards them and trying to maintain balance, often getting pulled back. If you spin in nice and tight, all you need to do is lean forward to throw. If you are already leaning yourself a bit it shouldn't be too much of a problem if your hips are close enough to uke.

Seoi was one of the throws. I found that when I was told to straighten up, I would end up going too high on the balls of my feet to compensate for the backward offbalance, but that made me susceptible to being pulled back. As you mention, my natural lean actually isn't much of a problem in and of itself.

Why not just seek professional help? You stated you were well read with regards to weightlifting, and that you checked your form in the mirror, but did you have a coach pointing problems out to you?

My little squatting misadventure occurred about three decades ago. What happened was that my lumbar muscles on the right side went into severe spasm, working in relays, spasming muscles tiring out and taking a rest while others went into spasm to take their place. I was twisted around into a corkscrew. After a lot of physical therapy and the ingestion of a lot of muscle relaxants, I was finally able to walk upright again. But the least little thing--bending a certain way or experiencing emotional stress--would set the lumbar muscles into spasm again. I found that I could ward off the spasms by religiously working the antagonistic muscle groups, doing hyperextensions and crunches to keep everything in balance. I wanted to do squats because they were a good excercise, but I just don't want to hit that "sweet spot" again and go into spasm, so squats be buggered.

If we think of the inclination of the torso while doing knee bends as being distributed on a bell-shaped curve, the average healty young person would probably be able to squat down to parallel with a reasonably erect torso. On one extreme, there are some Olympic snatchers who can drop down to rock bottom with their butts almost touching the floor, their backs ramrod straight, their arms locked straight up overhead supporting a monstrous amount of weight. On the other extreme, there are people like me who will never be able to hit parallel without their torsos being inclined pronouncedly forward. No amount of coaching can fix one's body simply not being able to get into a certain position.

I gave up on it over three decades ago when I crashed and burned with the barbell. I've conceded in a previous post that coaching might provide some marginal improvement, but I'm looking at this from a cost/benefit viewpoint. It's not as if I'm desperately obsessed with wanting to be a powerlifter and need to get the squat business worked out or that I'm some elite Olympic judoka whose game might be improved enough to matter by straightening the inclination of my torso a few degrees. It appears that I'm capable of adapting my judo to my natural posture, and the question is whether the cost of a coaching regimen would be worth whatever marginal improvements in posture such a regimen might produce.

The academic question of how much my posture might be improved has piqued my curiosity, however, and I'll keep the board apprised if I'm able to get an expert assessment of my situation.